Q7 to Q9
There is no consensus among researchers regarding what qualifies a
substance as a pheromone. While most agree on a basic definition of pheromones
as chemicals released by one individual of a species which, when detected by
another individual of the same species, elicit a specific behavioral or physiological
response, some researchers also specify that the response to pheromones must be
unconscious. In addition, the distinction between pheromones and odorants—
chemicals that are consciously detectedas odors---can be blurry, and some
researchers classify pheromones as a type of odorant. Evidence that pheromone
responses may not involve conscious odor perception comes from the finding that in
many species, pheromones are processed by the vomeronasal (or accessory olfactory)
system, which uses a special structure in the nose, the vomeronasal organ (VNO),
to receive chemical signals. The neural connections between the VNO and the
brain are separate from those of the main olfactory system, whose processing of
odorants triggers sensations of smell. But while the VNO does process many animal
pheromone signals, not all animal pheromones work through the VNO. Conversely,
not all chemical signals transmitted via the VNO quality as pheromones. For example,
garter snakes detect a chemical signal from earthworms—one of their favorite foods—via
the VNO, and they use this signal to track their prey.
Q.9 The primary purpose of the passage is to
A. compare and contrast the ways in which the vomeronasal organ
and the main olfactory systern process chemicals.
B. summarize the debate over the role the vomeronasal organ
plays in odor perception
C. present some of the issuesinvolved in the debate over
what constitutes a pheromone
D. propose a new definition of pheromones based on recent research
E. argue that pheromones should be classified as a type of odorant
這題答案 (E) 想請問一下該從何處判斷 謝謝